Quick Column Design Calculator
Design reinforced concrete columns with slenderness checks and P-M interaction per ACI 318.
Input Parameters
Enter column height, axial load, and moment. Column size is auto-calculated. Defaults: fixed-fixed, SD40 steel, My = 0.
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Get Started FreeHow This Column Calculator Works
This calculator designs reinforced concrete columns per ACI 318-19 (American Concrete Institute) and DPT 1008-61 (Thai Building Code). It evaluates slenderness effects on both major and minor axes, applies moment magnification factors (B1) for non-sway columns, and checks strength using P-M interaction criteria.
The design process includes: auto-sizing of the column cross-section based on axial demand, effective length calculation using k-factors for various end conditions (fixed-fixed k=0.5, fixed-pinned k=0.7, pinned-pinned k=1.0), slenderness evaluation against the ACI 318-19 limit of klu/r = 34, longitudinal bar selection satisfying rho_min (1%) to rho_max (8%), and tie design with proper spacing.
Disclaimer: This tool is intended for preliminary design estimation only. All results must be verified by a licensed professional engineer before use in construction. The engineer of record bears full responsibility for the final design.